1. Field of the Invention
The present invention relates to a photocathode in which light transmitted through a light transparent member is incident on a photocathode plate so that photoelectrons are emitted, an electron tube including the photocathode, and a method of assembling the photocathode.
2. Related Background Art
Such techniques according to the prior art include an electron tube disclosed in Japanese Patent Laid-Open No. 2002-42636 (Reference 1). In the electron tube disclosed in Reference 1, a photocathode plate is sandwiched between a faceplate and a supporting plate, and a pin embedded in the faceplate is joined with the supporting plate, so that the photocathode plate is fixed to the faceplate. In a case where this electron tube is used as a field assist type photocathode for detecting light with a long wavelength, when the pin and the supporting plate are formed of conductive materials, a bias voltage can be applied to the photocathode plate through the pin and the supporting plate.
A field assist type photocathode described above is also disclosed, for example, in Japanese Patent Laid-Open No. Hei 8-255580 (Reference 2). The photocathode plate of the field assist type photocathode disclosed in Reference 2 is fixed to the inner surface of the body of an electron tube by means of adhesive.